BEFORE YOU RESIGN, do not plan something stupid that makes people angry in your company. Gather as much information and read all your company policies if possible before the exit.

To have good relationship with your next employer and keep communication with them during your notice period and do not overpromise to leave early, in case you want that job badly please consider you have saving enough to pay your current company to offset the notice period.

Other than that, everything can be negotiated, do not be afraid and talk politely to all parties. Be honest if possible, of course sometime is not possible.

If you current employer/manager bully you, be calm and contact HR to assist you.